003 pairwise basic

// TEST: kernel.pairwise basic iteration
//
// Verifies:
// 1. kernel:init creates proper view with kernel branch
// 2. kernel:pairwise transforms into nested loops accessing k.ptr[i]/k.ptr[j]
// 3. The view flows through continuations properly

~import std/kernel
~import std/io

// Declare shape
~std/kernel:shape(Body) {
    mass: f64,
}

// Initialize with 3 bodies and run pairwise
~std/kernel:init(Body) {
    { mass: 1.0 },
    { mass: 2.0 },
    { mass: 3.0 },
}
| kernel k |> std/kernel:pairwise { k.mass += k.other.mass }
| computed c |> std/io:print.blk {
        pairwise complete, mass[0]={{ c[0].mass:f }}
    }